In a day of conflicting messages from the Federal Reserve that roiled financial markets, Chairman Ben Bernanke left some straightforward new clues about the central bank's plans for its $85 billion-a-month bond-buying program.

The Fed could take a first step toward reducing the program at one of its "next few meetings," Mr. Bernanke said, but he cautioned that he was reluctant to move prematurely or aggressively.